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History - the Invention of the Electric Motor 1800-1854

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History - the Invention of the Electric Motor 1800-1854 9/6/2018 History - The invention of the electric motor 1800-1854 Elektrotechnisches Institut (ETI) The invention of the electric motor 1800­1854 A short history of electric motors ­ Part 1 Univ.­Prof. Dr.­Ing. Martin Doppelbauer Summary With the invention of the battery (Allessandro Volta, 1800), the generation of a magnetic field from electric current (Hans Christian Oersted, 1820) and the electromagnet (William Sturgeon, 1825) the foundation for building electric motors was laid. At that time it was still open whether electric motors should be rotating or reciprocating machines, i.e. simulate a plunger rod of a steam engine. Worldwide, many inventors worked in parallel on this task ­ it was a "fashion" problem. New phenomena were discovered almost daily. Inventions in the field of electrical science and its applications were in the air. Often the inventors knew nothing about each other and developed similar solutions independently. National histories are shaped accordingly until present day. The following is an attempt to provide a comprehensive and neutral picture. The first rotating device driven by electromagnetism was built by the Englishman Peter Barlow in 1822 (Barlow's Wheel). After many other more or less successful attempts with relatively weak rotating and reciprocating apparatus the German­ speaking Prussian Moritz Jacobi created the first real rotating electric motor in May 1834 that actually developed a remarkable mechanical output power. His motor set a world record which was improved only four years later in September 1838 by Jacobi himself. His second motor was powerful enough to drive a boat with 14 people across a wide river. It was not until 1839/40 that other developers worldwide managed to build motors of similar and later also of higher performance. Already in 1833 the German Heinrich Friedrich Emil Lenz published an article about the law of reciprocity of the magneto­ electric and electromagnetic phenomena, i.e. the reversibility of electric generator and motor. In 1838 he provided a detailed description of his experiments with a Pixii­generator that he operated as a motor. In 1835 the two Dutchmen Sibrandus Stratingh and Christopher Becker built an electric motor that powered a small model car. This is the first known practical application of an electric motor. In February 1837 the first patent for an electric motor was granted to the US­american Thomas Davenport. However, all the early developments by Jacobi, Stratingh, Davenport and others eventually did not lead to the electric motors we know today. The DC motor was not created from these engines, but rather from the development of power generators (dynamometers). The foundations were laid by William Ritchie and Hippolyte Pixii in 1832 with the invention of the commutator and, most importantly, by Werner Siemens in 1856 with the Double­T­anchor and by his chief engineer, Friedrich Hefner­Alteneck, in 1872 with the drum armature. DC motors still have a dominant market position today in the low power (below 1 kW) and low voltage (below 60 V) range. The years 1885 until 1889 saw the invention of the three­phase electric power system which is the basis for modern electrical power transmission and advanced electric motors. A single inventor for the three­phase power system can not be named. There are several more or less well known names who were all deeply involved in the inventions (Bradley, Dolivo­Dobrowolsky, Ferraris, Haselwander, Tesla and Wenström). Today, the three­phase synchronous motor is used mostly in highly dynamic applications (for example in robots) and in electric cars. It was developed first by Friedrich August Haselwander in 1887. The highly successful three­phase cage induction motor was built first by Michael Dolivo­Dobrowolsky in 1889. Today, this is the most frequently produced machine in the power range of 1 kW and above. Timetable 1800 ­ 1834: First experiments with electromagnetical devices 1800 For the first time Allessandro Volta (Italian) produces a continuous electrical power (as opposed to a spark or static electricity) from a stack of silver and zinc plates. 1820 Hans Christian Oersted (Denish) finds the generation of a magnetic field by electric currents by observation of the deflection of a compass needle. This was the first time a mechanical movement was caused by an electric current. 1820 André­Marie Ampère (French) invents the cylindric coil (solenoid). https://www.eti.kit.edu/english/1376.php 1/13 9/6/2018 History - The invention of the electric motor 1800-1854 1821 Michael Faraday (British) creates two experiments for the demonstration of electromagnetic rotation. A vertically suspended wire moves in a circular orbit around a magnet. Rotating wire by Faraday, 1821 Photo courtesy of Division of Work & Industry, National Museum of American History, Smithsonian Institution 1822 Peter Barlow (British) invents a spinning wheel (Barlow's wheel = unipolar machine). Barlow's wheel, 1822 Philosophical Magazine, 1822, vol. 59 https://www.eti.kit.edu/english/1376.php 2/13 9/6/2018 History - The invention of the electric motor 1800-1854 1825­ William Sturgeon (British) invents the electromagnet, a coil of wires 1826 with an iron core to enhance the magnetic field. First electromagnet by Sturgeon, 1825 Transactions of the Society for the Encouragement of the Arts, Manufacturers and Commerce, 1824, vol. 43, pl. 3 1827­ Istvan (Ányos) Jedlik (Hungarian) invents the first rotary machine with 1828 electromagnets and a commutator. However, Jedlik publicly reported his invention only decades later and the actual invention date is uncertain. Still many Hungarians believe Jedlik has invented the electric motors. A functional model of his apparatus is displayed at the art museum in Budapest. Rotary device by Jedlik, 1827/28 Although this could actually be the first electric motor it has to be realized Photo: Wikipedia that this device had no influence on further development of electric machines. Jedlik's invention remained hidden for a long time and was not pursued by the inventor. The field of electrical engineering owes Jedlik nothing. Jedlik's electric car, 1827/28 Photo: Wikipedia https://www.eti.kit.edu/english/1376.php 3/13 9/6/2018 History - The invention of the electric motor 1800-1854 before Johann Michael Ekling, mechanic in Vienna, builds a motor according to the plans and ideas of Prof. Andreas von Baumgartner (Austrian physicist; 1830 since 1823 Professor of Physics and Applied Mathematics in Vienna). This apparatus was aquired in 1830 by the University of Innsbruck for the price of 50 fl c.m. The year of construction is unknown, but must have been before 1830 as the date of purchase is proven. Baumgartner's Engine, built by Ekling, before 1830 Photo courtesy of the University of Innsbruck, Museum of Experimental Physics, Ao. Univ. Prof. Mag. Dr. Armin Denoth. 1831 Michael Faraday (British) discovers and investigates electromagnetic induction, i.e. the generation of an electric current due to a varying magnetic field (the reversal of Oersted's discovery). Faraday lays the foundation for the development of the electric generator. 1831 Joseph Henry (US­American) finds the induction law independent of Faraday and builds a small magnetic rocker. He describes it as a "philosophical toy". In an article for the english Philosophical Magazine, in 1838 Englishman F. Watkins acknowledges Henry's device in detail and calls it the first electric motor ever known. This view extends to present day mainly in British literature. Henry's magnetic rocker, 1831 American Journal of Science, 1831, vol. 20, p. 342 https://www.eti.kit.edu/english/1376.php 4/13 9/6/2018 History - The invention of the electric motor 1800-1854 April Savatore dal Negro (Italian) builds a device that can lift 60 grams in one 1832 second by 5 centimeters and hence develops nearly 30 mW mechanical power. He was probably inspired by Henry's magnetic rocker and creates a similar reciprocating machine. However, Dal Negro's device can produce motion by a special gear arrangement. Dal Negro describes his experiments in a letter of April 1832 and later in a scientific paper „Nuova Macchina élettro­magnetica“ in March 1834. His devices are stored at the Museum of the History of Physics at the University of Padua. Unfortunately, they are not displayed. Dal Negro's electromagnetic pendulum, 1832 Annali delle Scienze de Regno Lombardo­Veneto, März 1834, pl. 4 July First public description of a rotating electric machine. 1832 The author is an anonymous letter­writer with the initials P.M. He has now been identified with high probability as the Irishman Frederick Mc­Clintock from Dublin. Michael Faraday, the recipient of the letter on 26 July 1832. publishes it immediately. For the first time a rotating electric machine is described in public. First description of a rotating electrical machine by P.M., 1832 Philosophical Magazine, 1832, p. 161­162 https://www.eti.kit.edu/english/1376.php 5/13 9/6/2018 History - The invention of the electric motor 1800-1854 July Hippolyte Pixii (French) builds the first apparatus for generating an 1832 alternating current out of a rotation . The device is presented publicly in September 1832 at a meeting of the Académie des Sciences. His description is printed already in the July issue of the Annales de Chimie. Pixii improved his device in the same year by adding a switching device. He can now produce a pulsating direct current. Pixii's first DC generator, 1832/33 F. Niethammer, Ein­ und Mehrphasen­Wechsel­strom­ Erzeuger, Verlag S. Hirzel, Leipzig 1906 1832 William Ritchie (British) reported in March 1833 of a device that he claimed to have built already nine month earlier in the summer of 1832. It is a rotating electromagnetic generator with four rotor coils, a commutator and brushes. Ritchie is therefore generally regarded as the inventor of the commutator.
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